Food for Dogs With History of Kidney Stones

The development of stones in the kidneys -- also called nephrolithiasis -- results from the presence of excessive minerals in the urine. These minerals lead to the formation of crystals in the urine that can turn into stones. As these stones are filtered through the kidneys, serious medical issues, including urinary obstructions, can result. Symptoms of kidney stones include frequent urinary tract infections, blood in the urine, painful urination and frequent urination that produces small amounts of urine. A veterinarian diagnoses the condition through a urinalysis and an ultrasound of the kidneys. A sample of the stones is also taken through a procedure called extracorporeal shock wave lithotripsy, which breaks up the stones with ultrasonic waves, according to PetMD.

Treatment for kidney stones in dogs involves the use of certain drugs to help dissolve the stones, dietary management and, in severe cases, surgery to remove the stones. Sometimes dietary management alone is enough, but it may also be used in conjunction with the other methods, depending on your veterinarian's diagnosis. Once the chemical composition of the kidney stone is determined, the vet will recommend dietary changes to eliminate the chemicals causing the stones. Excess amounts of mineral salts such as calcium, potassium, sodium, ammonia or carbonates in a dog's diet can all contribute to the formation of kidney stones, according to the VetInfo website. A diet that eliminates or is low in one or more of these elements can resolve the stones, if the vet determines this is the cause.

Diets high in vegetables and grains contain higher amounts of minerals and can lead to a more alkaline urine, which contributes to struvite stone formation. Specially formulated veterinary calculolytic diets have low amounts of magnesium, phosphorus and protein. These diets promote a more acidic urine and dissolve struvite stones, according to a study published in the October 2004 edition of "The Canadian Veterinary Journal." A low protein diet is also low in purine and can benefit dogs who suffer from urate stones. Calcium oxalate stones result from high levels of calcium in the diet and special veterinary diets are available that have low levels of calcium to feed to a dog with these types of stones.

To flush out the stones from the kidneys and prevent the formation of new stones of all types, a diet high in moisture is recommended. Canned dog food should be fed instead of dry kibble, which contains high amounts of minerals. Chicken or beef broth can be added to canned food to increase the moisture content. Adding sodium to your dog's food increases his water consumption and may be recommended by your veterinarian.

Special diets for specific types of stones have been developed by companies such as Hill's, Purina and Waltham; these are typically sold in veterinary offices and are available by prescription. Consult with your veterinarian on the type of diet he recommends for your dog's situation. Never feed additional treats or other foods to your dog while he is on a special, restricted diet. These foods can contain minerals that contribute to the formation of stones in his kidneys.